Statistics

Front 1

When computing the variance of a sample, the sumof the squared deviations, E (x-x)z, is divided by?

Back 1

The sample size minus one

Front 2

A company wants to graphically summarize in onechart the number of employees it has in each of its five decisions. What type of chart would be appropriate forthis purpose?

Back 2

bar chart

Front 3

A manufacturer claims to have built a homestereo speaker that is 4 feet tall but uses an average of only 30 watts ofpower. A sample of 40 speakers from themanufacturer found that they used an average of 32 watts of power. The appropriate hypotheses to test themanufacturer’s claim are?

Back 3

Ho: M=30 versus HA:M>30

Front 4

If the alternative hypothesis states thatthe population mean is not equal to 3500, the rejection region will consist of?

Back 4

Two regions, one in the right tail and one inthe left tail.

Front 5

A 98% confidence interval for a populationproportion is determined to be 0.756 to 0.834. If the confidence level is reduced to 95%, the same data will produce aninterval that?

Back 5

is narrower

Front 6

If the correlation coefficient, r, is equal toone?

Back 6

The standard error of the estimate, Sz is zero.

Front 7

The expected value of a random variable is also?

Back 7

a weighted average

Front 8

A study if elementary schools in the Los AngelesUnified School District focused on the percentage of teachers in each schoolwith emergency credentials (x, in percent) and the average reading scores (y)of fourth grade students in that school. The least squares regression line was y=400-3x. If twenty percent of the teachers in prairieElementary in the San Fernando Valley have emergency credentials, you wouldexpect the average reading scores of the fourth grade students in prairieElementary to be?

Back 8

340

Front 9

Ten percent of the mail that arrives at apost office has insufficient postage attached. If a postal worker selects 15 pieces of mail at random, what probabilitydistribution should he use to calculate the probability that three pieces ofmail have sufficient postage?

Back 9

none of the above

Front 10

If the population is normal, the populationstandard deviation is known, and the sample size is ten, which table would youuse for calculating probability of the sample mean?

Back 10

normal

Front 11

If the null hypothesis is that the populationmean is equal to 30 and you conduct a test with a significance level of 0.05and get a p-value of 0.08, then?

Back 11

You cannot reject the null hypothesis.

Front 12

A researcher has taken a random sample of morethan two items. Compared with thepopulation standard deviation, the standard error of the mean is?

Back 12

Smaller than the population standard deviation.

Front 13

A manufacturer of children’s toys claims thatexactly 5% of all his producing are defective. When 500toys from today’s outputs were examined 0.8% were found to bedefective. The 500 toys is?

Back 13

the sample

Front 14

A researchers is studying registeredvoters in Los Angeles to see if they favor the city of Los Angeles beingdivided into boroughs (smaller governmental units within the structure of thecity). He asks 350 voters to tell him ifthey would vote for a plan that would implement a borough system in LosAngeles. Out of the 350, 235 said theywere in favor of the plan. Thepopulation is?

Back 14

All the voters in Los Angeles

Front 15

A market researcher has interviewed 80 heads ofhouse holds and recorded whether the person was never married, divorced,windowed, or married. The data is?

Back 15

qulitative

Front 16

A car dealer is studying his customers and thecars they buy. It is appropriate for himto use a mean to describe?

Back 16

The color of the car bought by a typicalcustomer.

Front 17

Given that a sample of 25 had E x=75, and E(x-x) squared =448, the mean and standard deviation are?

Back 17

x=3.0 and s=square root of 48/24

Front 18

A sample of dental offices found the numbers ofcavities filled in the last week to be as follows: 12, 4, 4, 12, 12, 10. The median number of cavities filled is?

Back 18

11

Front 19

Suppose that, in testing situation with apopulation that is normally distributed, the null hypothesis is that thepopulation mean is equal to 41. A sample of size 36 had a sample mean of 41 andsample standard deviation of 2. which of the following is correct?

Back 19

You cannot reject the null hypothesis

Front 20

A sampleof 100 receipts from a restaurant showed that 12 had errors. What is the 95% confidence interval for theproportion of all receipts that have error? Note that z 0.025= 1.96 and t0.025= 1.984 for 99 degrees of freedom?

Back 20

0.12 +- (1.96) square root of (0.12)(0.88)/100

Front 21

If you have data on product output and totalcost of production, you can estimate fixed and variable cost by using?

Back 21

linear regression

Front 22

The postal service has recently raised the priceof a first class stamp by three cents to 37 cents. While you were in the post office, you saw 30three cent stamps sold and 20 of the new 37 cents stamps sold. What was the average price paid for a stampwhile you were in the post office?

Back 22

16.6

Front 23

An investor has purchasedstock in a firm. The investor believesthat, at the end of the year, there is 0.10 probabilities that the stock willshow a $6,000 profit, a 0.30 probability that the stock will show a $4000profit and a 0.60 probability that the stock will show a $2000 loss. The expected profit is $600. If the best profit increases by $1000 from$6000 to $7000, the expected profit?

Back 23

Will increase by $100

Front 24

The number of hours in the lifetime of a lightbulb is a random variable of which type?

Back 24

continuous

Front 25

Which of the following in NOT an assumption thatis required for the use of the binomial formula?

Back 25

The trial are independent

The probability of success is the samefor every trial

Each trial has only two possibleoutcomes

The random variable is the number ofsuccess out of N trials

Front 26

A survey was conducted in July, 2002 of 200 ofthe 6000 CSUN business students. Thesurvey asked the questions: Are you taking BUS 301 in the fall? Twenty percentof the 200 students said yes. Using thisinformation?

Back 26

The college didn’t have enough information to besure of hoe many sections to schedule

Front 27

If a television rating service surveyed 800viewers and 700 watched American Idol, the population is?

Back 27

All television viewers

Front 28

You survey your friends and ask them which typeof movie (action, comedy, romance, horror) they prefer. Which of the following graphical displayswould be most appropriate to display the data?

Back 28

a bar chart

Front 29

A car manufacturer states on the window stickerof its new cars: 38 MPG Highway. This isan example of?

Back 29

a mean

Front 30

A study of the number of cars sold looked at thenumber of cars sold at 500 Dealers The smallest dealer had 11 cars sold and thelargest had 154 cars sold. If you were going to create a frequency distributionof the number of cars sold using six classes in your frequency distribution,which of the following might be a reasonable first class?

Back 30

0 to 24

Front 31

Give that a sample of 25 had ∑x = 75, and∑(x-x)² = 48 the mean and standard deviation are

Back 31

X = 3.0 and S = 48/24

Front 32

If you take a sample of size 24 from anormal population for which you do not know the population standard deviation and want to calculate a 95%confidence interval for the mean, which is not need?

Back 32

The value of Z0.025

Front 33

The expected value of a random variable isalso-- E(X)

Back 33

A weighted average

Front 34

The retail price of a product is $5 per unit& the cost of production is $2 per unit. If the expected number of unitsold is 4, the expected profit will be

Back 34

12 ($5 profit per unit - $2 cost per unit = $3 * 4 unit sold = 12)

Front 35

Is not assumption that is required forthe use of binomial formula?

Back 35

. The trails are independent

The probability of success is the sameforever trail.

Each trail has only 2 possibleoutcomes

The random variable is the number ofsuccesses out of a trails

Front 36

You are measuring the lifetime of a light bulb.Which of the following might be the distribution of this random variable?

Back 36

normal

Front 37

If the P value is less then , you

Back 37

Should reject the nullhypothesis.

Front 38

Because of the variation in the measuredcontents of a can of cola,

Back 38

The average contents of a sample of 10 cans willgive us the average contents for the day’s production of 100,000 cans.

Front 39

A manufacturer of children’s toy claims thatexactly 5% of all his products are defective. When 500 toys from today’s outputwere examined, 8% were found to be defective. What is the parameter?

Back 39

. The % of all the toys made thatare defective.

Front 40

X claims that the average box of Xcontains 12 ounces. You bought 1 box at each 5 different grocery stores. Theweights were 13.1, 11.6, 12.1, 12.3 & 11.9 ounces. The mean weight of the 5 boxes was 12.2ounces.

Back 40

none of the above

Front 41

A car manufacturer is studying the relationshipbetween the weight of its vehicles and the mileage they get in city driving.Which following would an analyst for the company construct to aid in thisstudy?

Back 41

The least squares regression line.

Front 42

Which of the following is NOT quantitative date?

Back 42

Whether a driver buys premium gasoline or not

Front 43

A basketball player scored 12, 25, 16, & 13points in her last 4 games. What is the mean number of points per game shescored during this period?

Back 43

16.5

Front 44

The sample 10, 18, 20 has a standarddeviation of

Back 44

5.29 [(36+4+16) ÷ 2] = 56 ÷ 2 = √28 = 5.29

Front 45

Which of the following is NOT one of the stepsin hypothesis testing

Back 45

Choose a probability for your type ll error.

Front 46

An urban planner wished to determine whetherthere is sufficient evidence to conclude that the mean family income in the SanFernando Valley exceeds $38000. When the urban planner collects data on familyincomes, he would –

Back 46

Use a one-tailed test with thealternative to the left (less $38000)

Front 47

You took a sample of size 21 from a normaldistribution with a known standard deviation, . In order to find a 90%confidence interval for the mean, You need to find

Back 47

The mean of the sample and the value of Z withan area of 5% in the left tail

Front 48

A study was conducted in Malibu on the value ofa house (Y, in thousands of dollars) as it relates to the distance the house isfrom the beach (X, in miles). The result was the regression equation, Y=800-20X. In the equation, the number 20 represents.

Back 48

For each extra mile a house is from the beach,the price drops by $20,000

Front 49

The probability distribution of Z is:

X 1, 2, 3, 4

P(X) .30, .35, .20, .15

What is the expected number of childrenin a randomly selected Canadian household? Let X represent the number ofchildren in Canadian household.

Back 49

2.2

Front 50

A sales representative make 3 in person visitsto customers every morning. Out of the 3 visits, she will make either 0, 1.3 or3 sales. The probabilities are 0.2, 0.4, 0.3, and 0.1, respectively. For eachsale, she gets a commission of $100. Her expected commissions for one morning’svisits are

Back 50

130

Front 51

The binomial distribution is a distribution

Back 51

Which always takes integer values

Front 52

A random variable is found by sampling classesat CSUN and counting the number of those classes with over 200 studentsenrolled. Which of the following distributions might be the distribution ofthis random variable.

Back 52

normal

Front 53

For a given hypothesis test, the nullhypothesis can be rejected at the 0.05 level of significance. We can infer thatP-value.

Back 53

Is less than 0.05

Front 54

When you increase the size of your sample from apopulation,

Back 54

You decrease the standard deviation of the sample mean

Front 55

A summary measure computed from a sample is a

Back 55

Statistic

Front 56

A manufacturer of children’s toys claims thatexactly 5% of all his products are defective. When 500 toys from today’s outputwere examined, 8% were found to be defective. What is the sample?

Back 56

500 toys

Front 57

A student took a sample of 25 textbooks from thebookstore and recorded the costs of the books. The student wants to knowwhether the mean cost of all textbooks is greater than $75. The student should,

Back 57

Test the null hypothesis that the mean cost ofall textbooks is equal to $75.

Front 58

When computing the variance of a sample, the sum of the squared deviations, E(x-x)z, is divided by?

Back 58

The sample size minus one (this the right one)

Front 59

Reasons to calculate the mean of a data set

Back 59

find measure of location

Front 60

Sample of dental cavities filled were 12, 4, 4,12, 12, 10 what is median.

Back 60

11

Front 61

If alt. hypothesis states pop. Mean= 3500,rejection region will be…

Back 61

left and right region

Front 62

Regression equation -1=5-2x, predicted value ofy equals

Back 62

1 when x=2

Front 63

There is a .20 probability that stockwill profit 3000, .10 prob. That stock will profit 6000, .70 prob. -2000losses. What is expected profit?

Back 63

-200

Front 64

Retail = $5 , cost is $2. units sold = 4 what isprofit. Same as #8

Back 64

12

Front 65

Which is NOT characteristic of normaldistribution.

Back 65

mean is 0

Front 66

Top 15% of students get A. sample 4 from 200, tocomplete prob. That 2 of 4 got A’s, use:

Back 66

binomial dist.

Front 67

P value is > α you

Back 67

No, you cannot reject the nullhypothesis

Front 68

Summary measure computed from pop is a:

Back 68

statistics

Front 69

Sampled 20 banks and recorded rates for 30yrs. Data is:

Back 69

qualitative - data that can be separatedinto different categories distinguished by some nonnumeric characteristic

Front 70

Computing variance of sample sum of the squaredeviation is divided by

Back 70

Population size minus one

Front 71

Distributing of home prices is often positivelyskewed (right). Its likely that

Back 71

Mean greater than median

Front 72

Standard deviation of population A is greaterthan the standard deviation of population B, all other things equal theconfidence interval for the mean A should be

Back 72

Wider then the confidence interval for the meanof B

Front 73

Which of the following statement is correct?

Back 73

Expected value of a randomvariable is the long run average assuming he experiment is repeated many times.

Front 74

The correlation coeffiect “r”

Back 74

Measure the relativerelationship between 2 variable

Front 75

Hypothesis test, the null hypothesis can berejected at the 0.05 level of significance. We can conclude that the p-value

Back 75

Is less than 0.05

Front 76

Sample of 20 CSUN students found the age of eachstudent……

Back 76

The highest age is at leasttwice the average age.

Front 77

A care manufacturer states on the window stickerof its new care: 38 MPG highway. This is an example of:

Back 77

mean

Front 78

Manufacturer of child toy claims exactly 5% ofall his products are defected. 500 toyswere examined 8% were defective. Population of interest?

Back 78

Proportion

Front 79

A study of the number of cars sold lookedat the number of cars sold at 500 dealers. The smallest dealer had 11 carssold. The largest had 159 cars sold. If you were to make a frequencydistribution of the # of cars sold using six classes. In your frequencydistribution which might be a reasonable first class?

Back 79

0 to 24

Front 80

If you have data on product output and totalcost of production, you can estimate fixed and variable cost by using: Whatkind of distribution.

Back 80

Linear regression

Front 81

When you increase the size of your sample from apopulation you

Back 81

You decrease the standarddeviation of the sample mean

Front 82

A car manufacture states on the window stickerof its new cars 38 mpg hwy. This is an example of a:

Back 82

mean

Front 83

A market researcher has interviewed 80 heads ofhouseholds and recorded wehter there was a DVD player in the household. Thedata is:……

Back 83

the information from the 80 ppl

Front 84

Ritzier Crackers claims that the average box ofRitzier Crackers contains 12 ounces. You bought one box at each of 5 differentgrocery stores. The weights are 12.1, 11.6, 12.3, 11.9, 13.1 ounces. The meanweight of the boxes was 12.2 ounces. The sample is….

Back 84

The 5 weights above

Front 85

The weighted average of all possiblevalues of x, where the weights are the probabilities of occurrence of thosevalues, is referred to as:

Back 85

Expected value

Front 86

If you have data on product output and totalcost of production, you can estimate fixed and variable cost by using:

Back 86

Linear regression

Front 87

Sample size 25 normal population had amean 75 standard deviation of 12 95% confidence (note z.025 = 1.96, t .025 =2.064 for 24 degree of freedom

Back 87

Should be 3 Plus/minus1.96*12/sqrt(25

Front 88

Correlation coefficient is zero not possiblewhen

Back 88

Points fall on a straight line with a negativeslope

Front 89

Random sample 400 household 220

Back 89

Ho=.50 vs. Ha T>.50 p-value is .0225

Front 90

Car manufactures ….between ….. its velocity

Back 90

Least square regression line

Front 91

If CNN had a poll with yes and no answers theycan grab all the data and use a

Back 91

The sample proportion

Front 92

I-5 freeway between Los Angeles and San Diego8,200 people ………

Back 92

28,500 ± (1.96) 8,200/ square root 24

Front 93

Expected return from a bet of $1.00casinos is

Back 93

In the long run you will lose $6 every dollaryou bet

Front 94

A researcher is studying CSUN students. It is looking at all CSUN students of allages what kind of data is this?

Back 94

Population

Front 95

To display a proportion of studying in eachoption of the BS in Business administration what would you use?

Back 95

Pie chart

Front 96

Y = 8-0.4X X=Price, Y=Sales, The number 0.4 represent?

Back 96

If increase by 1 sales,decrease by 0.4

Front 97

X 0 1 2

P(x) 0.1 0.6 0.3

The expected value of X, E(x) is

Back 97

1.2

Front 98

You are eating in steak house, which is notqualitative data?

Back 98

Size of you 12 ounce.

Front 99

Which of the following is NOT measure oflocation or central tendency?

Back 99

Range

Front 100

Not an appropriate alternative hypothesis?

Back 100

none

Front 101

Reason to calculate the mean

Back 101

Measure of the location or central trend ofnumbers in the data set

Front 102

Simple linear regression involves the use of

Back 102

One independent and one dependent variable

Front 103

The expected value of a random variable is thelong run average value assuming the experiment is repeated many times

Back 103

true

Front 104

A researcher for a major bank has sampled 20other banks and recorded their current interest rates for 10 yearmortgage. The data is

Back 104

continuous